Specifications

Apple II Technical Notes
6 of 4 #77: Print Manager & AppleTalk Configuration Files
The ATInit File Format
The AppleShare Programmer’s Guide for the Apple IIGS shows the file format of the ATInit file
as it is stored on an AppleShare boot volume. However, the file format of ATInit is not always
as shown in that manual. In all cases, ATInit will contain the three required data fields
UserName, PrinterFlags, and PrinterTuple at the end of the file. Before those data
fields, ATInit may also contain executable code or additional data fields. Since the three
required data fields are directly before ATInit’s end-of-file (EOF), you can find them relative to
ATInit’s EOF using the displacements listed in Table 1.
Displacement to
ATInit EOF Size Field Name Description
133 33 Bytes UserName A Pascal-type string containing the default User
Name. It consists of a length byte followed by
up to 31 bytes of ASCII data and a single,
unused byte. This field is always 33 bytes long.
100 Byte PrinterFlags This is the Flags field used by the Remote Print
Manager’s default network printer.
99 99 Bytes PrinterTuple This field specifies the name of the default
network printer used by the Remote Print
Manager. The PrinterTuple field is in
standard Name Binding Protocol (NBP) format.
This field is always 99 bytes long.
Table 1–Offsets of Required Data Fields
If the ATInit file is on an AppleShare server, it will have 6 additional data fields (PathVolID,
PathDirID, Path, PrefixVolID, PrefixDirID, and Prefix) directly before the three
required data fields. These fields can also be found relative to ATInit’s EOF using the
displacements listed in Table 2.
Displacement to
ATInit EOF Size Field Name Description
275 Word PathVolID The Volume ID number of the user’s AppleTalk
startup application.
273 Long PathDirID The Directory ID number of the user’s
AppleTalk startup application.
269 65 Bytes Path The Pathname of the user’s AppleTalk startup
application.
204 Word PrefixVolID The Volume ID number of the user’s AppleTalk
default prefix.
202 Long PrefixDirID The Directory ID number of the user’s
AppleTalk default prefix.
198 65 Bytes Prefix The user’s AppleTalk default prefix.
Table 2–Offsets of Optional Data Fields
The displacements in Tables 1 and 2 can be used with the GS/OS SetMark call to move the file
mark to the beginning of any of the above fields. The SetMark call’s base field should be set
to $0001 so the mark will be set equal to EOF minus the displacement.